Place CPU in P0 state while idle

[fw/altos] / ao_task.c

diff --git a/ao_task.c b/ao_task.c
index 4fb8405595c5b4a1ffc0fc68e1844f243bb07be2..b69f51ee432f61c5b0f408df01c5123301f11e00 100644 (file)
--- a/ao_task.c
+++ b/ao_task.c
@@ -25,13 +25,14 @@ __data uint8_t ao_cur_task_index;
 __xdata struct ao_task *__data ao_cur_task;
 
 void
-ao_add_task(__xdata struct ao_task * task, void (*start)(void))
+ao_add_task(__xdata struct ao_task * task, void (*start)(void), __code char *name) __reentrant
 {
        uint8_t __xdata *stack;
        if (ao_num_tasks == AO_NUM_TASKS)
                ao_panic(AO_PANIC_NO_TASK);
        ao_tasks[ao_num_tasks++] = task;
        task->task_id = ao_num_tasks;
+       task->name = name;
        /*
         * Construct a stack frame so that it will 'return'
         * to the start of the task
@@ -94,9 +95,9 @@ ao_yield(void) _naked
        
        if (ao_cur_task_index != AO_NO_TASK_INDEX)
        {
-       uint8_t stack_len;
-       __data uint8_t *  stack_ptr;
-       __xdata uint8_t * save_ptr;
+               uint8_t stack_len;
+               __data uint8_t *stack_ptr;
+               __xdata uint8_t *save_ptr;
                /* Save the current stack */
                stack_len = SP - (AO_STACK_START - 1);
                ao_cur_task->stack_count = stack_len;
@@ -113,19 +114,29 @@ ao_yield(void) _naked
        /* Find a task to run. If there isn't any runnable task,
         * this loop will run forever, which is just fine
         */
-       for (;;) {
-               ++ao_cur_task_index;
-               if (ao_cur_task_index == ao_num_tasks)
-                       ao_cur_task_index = 0;
-               ao_cur_task = ao_tasks[ao_cur_task_index];
-               if (ao_cur_task->wchan == NULL)
-                       break;
+       {
+               __pdata uint8_t ao_next_task_index = ao_cur_task_index;
+               for (;;) {
+                       ++ao_next_task_index;
+                       if (ao_next_task_index == ao_num_tasks)
+                               ao_next_task_index = 0;
+
+                       ao_cur_task = ao_tasks[ao_next_task_index];
+                       if (ao_cur_task->wchan == NULL) {
+                               ao_cur_task_index = ao_next_task_index;
+                               break;
+                       }
+
+                       /* Enter lower power mode when there isn't anything to do */
+                       if (ao_next_task_index == ao_cur_task_index)
+                               PCON = PCON_IDLE;
+               }
        }
 
        {
                uint8_t stack_len;
-               __data uint8_t *  stack_ptr;
-               __xdata uint8_t * save_ptr;
+               __data uint8_t *stack_ptr;
+               __xdata uint8_t *save_ptr;
 
                /* Restore the old stack */
                stack_len = ao_cur_task->stack_count;
@@ -168,16 +179,16 @@ ao_yield(void) _naked
        _endasm;
 }
 
-int
+void
 ao_sleep(__xdata void *wchan)
 {
        __critical {
-       ao_cur_task->wchan = wchan;
+               ao_cur_task->wchan = wchan;
        }
        ao_yield();
 }
 
-int
+void
 ao_wakeup(__xdata void *wchan)
 {
        uint8_t i;
@@ -188,9 +199,25 @@ ao_wakeup(__xdata void *wchan)
 }
 
 void
-ao_start_scheduler(void)
+ao_task_info(void)
 {
+       uint8_t i;
+       uint8_t pc_loc;
+       __xdata struct ao_task *task;
+
+       for (i = 0; i < ao_num_tasks; i++) {
+               task = ao_tasks[i];
+               pc_loc = task->stack_count - 17;
+               printf("%12s: wchan %04x pc %04x\n",
+                      (char *) task->name,
+                      (int16_t) task->wchan,
+                      (task->stack[pc_loc]) | (task->stack[pc_loc+1] << 8));
+       }
+}
 
+void
+ao_start_scheduler(void)
+{
        ao_cur_task_index = AO_NO_TASK_INDEX;
        ao_cur_task = NULL;
        ao_yield();